Fixing possible null-pointer dereferences

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4524 43c1dc8c-776e-4df2-8ef1-6e829299be21
Fixing possible null-pointer dereferences

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4525 43c1dc8c-776e-4df2-8ef1-6e829299be21
Fixing free issue on return from re-alloc

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4526 43c1dc8c-776e-4df2-8ef1-6e829299be21
Fixing possible null-pointer dereferences / Removed unnecessary retain/release

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4527 43c1dc8c-776e-4df2-8ef1-6e829299be21